Metamath Proof Explorer

Theorem dmuz

Description: Domain of the upper integers function. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Assertion dmuz 
|- dom ZZ>= = ZZ

Proof

Step Hyp Ref Expression
1 uzf 
 |-  ZZ>= : ZZ --> ~P ZZ
2 1 fdmi 
 |-  dom ZZ>= = ZZ